Outrigger float mounting

ABSTRACT

An extensible outrigger arrangement of the type where the float is pivotally mounted on the rod of the vertical cylinder and cammed to a vertical storage position upon retraction is provided with cam plates pivotal coaxially with the float. A pair of torsion springs between the cam plates and float maintain the parts in normal relative positions, but allow the float to pivot should an obstruction be encountered when the outrigger beam is extended while the float is in its vertical position.

United States Patent 1191 Hornagold [4 1 Aug. 26, 1975 l l OUTRIGGERFLOAT MOUNTING [75] Inventor: John T. Hornagold, Roseville, Minn [73]Assignee: Bucyrus-Erie Company, South Milwaukee, Wis

122 Filed: May 16, 1974 2|1 Appl.No.:470,39l

[52] U.S. Cl i. 280/1505; 212/[45 [Sll Int. Cl. B605 9/10 [58} Field ofSearch.1.,...4.,.v....r. 280/1505; 2l2/l45; 2l4/l4l [56] ReferencesCited UNITED STATES PATENTS 3,754 777 8/1973 Riggs .i 280/1505 3,767,226lO/l973 Stcphcns v. 28U/l50.5

1825280 7/l974 Myers 280N505 Primary Examiner-Robert R. Song Atrorney,Agent, or Firm-Quarles & Brady [57] ABSTRACT An extensible outriggerarrangement of the type where the float is pivotally mounted on the rodof the vertical cylinder and cammed to a vertical storage position uponretraction is provided with cam plates pivotal coaxially with the float.A pair of torsion springs between the cam plates and float maintain theparts in normal relative positions, but allow the float to pivot shouldan obstruction be encountered when the outrigger beam is extended whilethe float is in its vertical position.

4 Claims, 5 Drawing Figures PATENT [[1 M826 1975 OUTRIGGER FLOATMOUNTING BACKGROUND OF THE INVENTION This invention relates toextensible outriggers for truck cranes and the like, and moreparticularly to outriggers with self-storing floats of the type shown inthe copending application of John T. Hornagold, Ser. No. 412,374, filedNov. 1, 1973 for Mounting for Vertical Outrigger Cylinder."

Truck cranes and similar machines are commonly provided with outriggerscomprising extensible and retractable horizontal beams and verticalcylinders mounted on the ends of the beams and provided with groundengaging floats. When the floats are in their horizontal workingpositions they extend laterally substantially beyond the verticalcylinders; and, particularly for truck cranes where travel width is aserious problem, it is desirable to have some means for moving thefloats to retracted or stored positions it would of course be possibleto remove the floats entirely, but this can be very difficult and timeconsuming, particularly for large machines with heavy floats. In theaforementioned application Ser. No. 412,374, to which reference may behad for further description, the problem is solved by providing acamming mechanism which causes the float to pivot to a vertical storedposition alongside the vertical cylinder when the rod of the verticalcylinder is retracted.

The noted arrangement is highly satisfactory, but it does present aproblem in that, when the floats are in vertical position they mayextend substantially below the vertical cylinder and the beam. When amachine is being set up, the beam is usually at least partially extendedbefore the rod of the vertical cylinder is extended, and it is entirelypossible that the lower edge of the float will run against the ground orsome obstruction during this movement. Because of the cammingarrangement, the float is necessarily in direct contact with theremainder of the assembly, and running against any obstacle can causetwisting forces which can result in serious structural damage.

SUMMARY OF THE INVENTION The present invention contemplates an improvedoutrigger float mounting arrangement in which the foregoing problem isovercome by, in effect, making the cam portion of the float relativelymovable with respect to the float proper and providing resilient meansthat normally holds the respective parts in working position but thatcan be overridden to allow the float to pivot and ride over obstructionsand then return to stored position. In the preferred embodiment, this isaccomplished by providing cam plates which are pivotally mountedcoaxially with the pivotable float and torsion springs effectivelyinterposed between the cam plates and the float proper. This permitsrelative movement between the float and earn plates if an obstruction isencountered, but once the float has moved over the obstruction. thesprings will automatically cause the parts to return to their normalrelative positions. The arrangement of the invention is highly effectiveand durable, but is also relatively inexpensive and easy to manufacture, assemble, maintain and use.

Other objects and advantages will appear from the description to follow.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial schematic view ofa truck crane having outriggers incorporating the float mountingarrangement of the invention;

FIG. 2 is a fragmentary side view ofa single outrigger of the machine ofFIG. 1, showing the float in stored position;

FIG. 3 is a fragmentary side view similar to FIG. 2,

but showing the float in horizontal working position;

FIG. 4 is a fragmentary side view similar to FIG. 2, but showing thefloat pivoted to an intermediate position that might be assumed inpassing over an obstacle; and

FIG. 5 is a view in cross-section, partially broken away, through theplane 55 shown in FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT In FIG. I, the reference numeral1 designates generally a conventional truck crane with a wheeled carrierand revolving upper works. While the invention is particularlysatisfactory for such machines, however, it should be understood that itis applicable to any construction or excavating machine or other machineor equipment of any type where outriggers are provided.

The outrigger assembly includes a transverse box housing 2 which isconnected in conventional fashion to the underside of the carrier frame.As is usual, the housing is dual, comprising two adjacent and parallelsections, one for a beam extending to one side of the machine and theother for an oppositely extending beam, and there are two such dualoutrigger assemblies, one toward the front and one near the rear of thecarrier. For the sake of simplicity only one beam and vertical cylinderare shown in detail, but the other three outriggers are the same.

The outrigger assembly includes a horizontally disposed outrigger beamassembly 3 which is extensibly and retractably received in theassociated section of the housing 2 and in the preferred embodimentcomprises two telescoping sections, an inner beam 4 and an outer beam 5,which are actuated by a hydraulic cylinder (not shown). A double acting,hydraulic, vertical cylinder 6 carries a self-storing float 7 and isconnected to the outer beam by means of a two-pin mounting arrangementdesignated generally by the reference numeral 8. Further disclosure ofthe mounting arrangement can be had by reference to the application ofHornagold, Ser. No. 412,374, filed on Nov. 1, 1973. The presentinvention, of course, does not necessitate the use of this particularmounting arrangement which is shown for illustrative purposes only.While a two section beam is shown, the invention is equally applicableto outrigger assemblies with single section beams or beams with morethan two sections.

As previously indicated, the float 7 is self-storing; and it is shown inits stored position and its horizontal working position in FIGS. 2 and3, respectively. The float 7 is pivotally connected to the rod 9 of thecylinder 6 by means of a pin 10 which is pivotally received transverselythrough the bifurcated outer end of the rod 9 and extends transverselypivotally through a bifurcated mounting bracket 11 fixed to the topsurface of the float pad 12. A pair of parallel plates I3 which serve ascam follower means are bolted to the pin 10 to be pivotable coaxiallywith the float 7. The cam plates 13 are engageable with a bar cammingmember 14 which is fixed to the end of the outer beam section 5 of thehorizontal cylinder. A pair of torsion springs 15 are wound around thepin 10. Each spring 15 has one end trapped by a stop 16 on a respectiveone of the cam plates 13 and its other end trapped by an upstanding stopbar 17 fixed to and extending substantially across the pad 12.

The float 7 is pivotal with respect to the rod 9 by virtue of thebracket 11 being mounted on the pin 10, the pin defining an axis ofrotation that is generally parallel to the length of the machine 1 andhorizontally transverse to the line of movement of the beam 3 duringextension and retraction. The cam plates 13 are pivotable about the sameaxis; in the preferred embodiment this is accomplished by fixing them tothe pivotable pin 10, but they could be pivotably mounted. The float 7and plates 13 are also coaxially pivotable with respect to one another,but are normally held in relative working positions, as seen best inFIG. 3, by the springs which move them in opposite directions; referringto FIG. 3, the float 7 is moved in a clockwise direction and the plates13 are moved in a counterclockwise direction. Relative pivotal movementin this fashion is limited by engagement of the plates 13 with the stop17, as seen in FIG. 3.

During working the float 7 will be in the position shown in FIG. 3,except that the rod 9 will have been extended further so that the pad 12engages the ground. When the machine is to be moved, the rod 9 isretracted and the float moves to the position shown in FIG. 3, at whichpoint the edges of the cam plates 13 come into contact with the cammingmember 14. Further retraction of the rod 9 will cause the edges of theplates 13, which are appropriately contoured, to ride along the bar 14so that the entire float assembly, including the cam plates 13, pivotsclockwise to the stored position shown in FIG. 2 where the pad 12 isvertical and alongside the outer side of the cylinder 6; the springs 15hold the float 7 and plates 13 in their normal relative positions duringthis movement. With the float assembly in this stored position theoverall width of the outrigger assembly is reduced significantly, thisfeature being particularly desirable for large machines with largefloats.

It is desirable to allow the float limited movement in all directions toallow compensation for minor ground irregularities, and a generallyconventional ball bushing arrangement is preferred. As can be seen inFIG. 5, a ball member 18 is fitted on the pin 10, and the outer end ofthe rod 9 is bifurcated to receive a socket member 19.

In operation, the beam assembly 3 is usually first extended, at leastpartially, and the rod 9 is then extended so that the pad 12 engages theground, the float 7 being freed to assume its working position as therod 9 extends. For travel to another site, the rod 9 is usuallyretracted first, which moves the float 7 to its stored position, and thebeam assembly 3 is then retracted.

It is when the beam 3 is being extended for setup with the float 7vertical that the relative movement allowed between the float 7 andplates 13 becomes important. That is, the pad 12 extends substantiallybelow the cylinder 6 and beam 3 when it is in stored position, andshould the machine have settled as the result of being on soft ground,or if there are any other obstacles to the side of the machine, it islikely that the lower edge of the pad 12 will come against the obstacle.Absent the allowed relative movement, the resulting twisting forceswould be transmitted directly to the cylinder 6 and/or the cam member14, which could result in serious damage or breakage. With the mountingof this invention, however, the entire float 7 is able to pivot,temporarily overriding the springs 15, to the intermediate positionshown in FIG. 4, as the result of which it can ride over the obstacle.As soon as the pad 12 is past the obstacle, however, the springs 15 willautomatically cause the parts to return to their normal relativepositions.

Relative pivotal movement of the float 7 and plates 13 is limited byengagement of the plates with the pad as seen in FIG. 4, but it ispossible with the arrangement of the invention to provide several inchesor more of additional clearance capability which is sufficient toprevent damage in almost all situations should there be higherobstacles, they will be visible to the operator so that the situationcan be remedied prior to extension of the beam 3. Thus, the inventionprovides a relatively simple but highly effective way of overcoming acommon and serious problem.

The preferred embodiment shown and described provides all of thefeatures and advantages discussed above, but noted and other variationsare possible without departure from the spirit of the invention. Theinvention is not, therefore, intended to be limited by the showing ordescription herein, or in any other manner, except insofar as mayspecifically be required.

I claim:

1. In an extensible outrigger assembly comprising an extensiblehorizontal beam, a vertical cylinder mounted on the outer end of thebeam that has a downwardly extensible and upwardly retractable rod, afloat pivotally mounted on the outer end of the rod to be movablebetween a horizontal working position and a vertical stored positionalongside the vertical cylinder, a camming member mounted on theoutrigger assembly near the vertical cylinder rod, and a cam followermounted on the float that engages the camming member upon retraction ofthe rod to cause the float to pivot from working to stored position theimprovement wherein:

the cam follower is relatively movably mounted on the float; and thereis a resilient connection between the float and cam follower whichnormally holds the float and cam follower in normal relative positionsbut which can be overridden to allow the float to pivot from its storedposition toward its working position so that it can ride over anobstacle encountered when the beam is extended with the float in storedposition, the resilient connection serving to return the float and camfollower to their normal relative positions after the obstacle has beenpassed.

2. An outrigger assembly according to claim 1, wherein: there is amounting pin extending through the outer end of the rod horizontallytransverse to the line of movement of the beam during extension thereof,and the float includes an upwardly extending mounting bracket that ismounted on the pin; and the cam follower comprises a cam plate that ismounted on the pin and that has a contoured edge that is engageable withthe camming member, the float and cam plate being 6 their normalrelative positions.

4. An outrigger assembly according to claim 3 wherein: one end of thespring is engaged against an upstanding stop on the float, the cam platebeing engageable with the stop to limit the opposite pivotal movementprovided by the torsion spring.

1. In an extensible outrigger assembly comprising an extensiblehorizontal beam, a vertical cylinder mounted on the outer end of thebeam that has a downwardly extensible and upwardly retractable rod, afloat pivotally mounted on the outer end of the rod to be movablebetween a horizontal working position and a vertical stored positionalongside the vertical cylinder, a camming member mounted on theoutrigger assembly near the vertical cylinder rod, and a cam followermounted on the float that engages the camming member upon retraction ofthe rod to cause the float to pivot from working to stored position theimprovement wherein: the cam follower is relatively movably mounted onthe float; and there is a resilient connection between the float and camfollower which normally holds the float and cam follower in normalrelative positions but which can be overridden to allow the float topivot from its stored position toward its working position so that itcan ride over an obstacle encountered when the beam is extended with thefloat in stored position, the resilient connection serving to return thefloat and cam follower to their normal relative positions after theobstacle has been passed.
 2. An outrigger assembly according to claim 1,wherein: there is a mounting pin extending through the outer end of therod horizontally transverse to the line of movement of the beam duringextension thereof; and the float includes an upwardly extending mountingbracket that is mounted on the pin; and the cam follower comprises a camplate that is mounted on the pin and that has a contoured edge that isengageable with the camming member, the float and cam plate beingpivotable with respect to the rod and with respect to each other aboutan axis defined by the pin.
 3. An outrigger assembly according to claim2, wherein: the resilient connection comprises a torsion spring that iswound around the pin with its ends operatively engaged, respectively,with the float and cam plate, the torsion spring normally serving topivot the float and cam follower in opposite directions toward theirnormal relative positions.
 4. An outrigger assembly according to claim 3wherein: one end of the spring is engaged against an upstanding stop onthe float, the cam plate being engageable with the stop to limit theopposite pivotal movement provided by the torsion spring.